title: An international comparability study on quantification of total methyl cytosine content.
abstract: Various methods have been developed for quantitative analysis of DNA methylation. However, there is currently no reference analysis system regarding DNA methylation with which other analytical approaches can be compared and evaluated. A standard measurement system that includes reference methods and reference materials may improve comparability and credibility of data obtained from different analytical environments. In an effort to establish a standard system for measurement of DNA methylation, the Korea Research Institute of Standards and Science (KRISS) coordinated an international comparison study among different national metrology institutes. An initial stage of the study involved an intercomparison regarding quantitative measurement of total methyl cytosine contents in artificially constructed DNA samples. The measurement principle involved measurement of dNMP contents following enzymatic hydrolysis of DNA samples. Results of the study showed good comparability among four of five participants and close agreement with reference values assigned by the coordinating laboratory. Conflicting data from one participant may have resulted from incomplete hydrolysis of samples due to use of insufficient amounts of enzymes. These results indicate that comparable and accurate results can be obtained from different measurement environments if digestion conditions are controlled appropriately and valid calibration systems are employed.
authors.affiliation: Health Metrology Group, Korea Research Institute of Standards and Science, 1 Doryong-dong, Yusung-gu, Daejon 305-340, Republic of Korea.
authors.forename: Inchul
authors.initials: I
authors.lastname: Yang
authors.forename: Sook-Kyung
authors.initials: SK
authors.lastname: Kim
authors.forename: Daniel G
authors.initials: DG
authors.lastname: Burke
authors.forename: Kate
authors.initials: K
authors.lastname: Griffiths
authors.forename: Zena
authors.initials: Z
authors.lastname: Kassir
authors.forename: Kerry R
authors.initials: KR
authors.lastname: Emslie
authors.forename: Yunhua
authors.initials: Y
authors.lastname: Gao
authors.forename: Jing
authors.initials: J
authors.lastname: Wang
authors.forename: Carole A
authors.initials: CA
authors.lastname: Foy
authors.forename: Ana Carmen
authors.initials: AC
authors.lastname: Pardos-Pardos
authors.forename: Steve
authors.initials: S
authors.lastname: Ellison
authors.forename: Paula Jane
authors.initials: PJ
authors.lastname: Domann
authors.forename: Shin-Ichiro
authors.initials: S
authors.lastname: Fujii
authors.forename: Sang-Ryoul
authors.initials: SR
authors.lastname: Park
mesh_terms: D003596:Cytosine / Q000031:analogs & derivatives* / Q000032:analysis*; D019175:DNA Methylation; D003854:Deoxyribonucleotides / Q000737:chemistry; D019075:Electrophoresis, Capillary; D006868:Hydrolysis; D012015:Reference Standards
chemical_list: D003854:Deoxyribonucleotides; D003596:Cytosine